(1 of )Handler Debi DeShon directs her dog Popeye to sniff for invasive quagga and zebra mussels on a boat about to launch into Lake Sonoma on Thursday morning. Popeye, a 6-year-old chocolate lab, has never found a wild mussel in his searches at Lake Sonoma and Mendocino.

(2 of )Handler Debi DeShon directs her dog Popeye to sniff for invasive quagga and zebra mussels on a boat about to launch into Lake Sonoma on Thursday morning. Popeye, a 6-year-old chocolate lab, has never found a wild mussel in his searches at Lake Sonoma and Mendocino.

A consortium of government agencies with a stake in the health of Lake Sonoma and Lake Mendocino are putting the finishing touches on a mandatory boat inspection strategy they hope will hold off the scourge of invasive mussels already fouling waterways around the state.

The proposed plan, expected to be up and running next spring, will require adjustments and patience on the part of recreational boaters, officials say.

But it’s believed to be the only way to ensure the tiny but destructive shellfish that have infested 30 water bodies in California don’t get a toehold on the North Coast, they said.

“The threat — besides the drought — of quagga mussels taking hold in either of the two lakes is one of the most significant facing us today,” Sonoma County Supervisor Mike McGuire said.

“Once it takes hold, it’s too late,” he said. “It impacts the lake’s ecosystem, it impacts water transmission infrastructure, and it will impact our local economy.”

Many boaters who have visited either of the lakes in the past three years already are somewhat familiar with the risk posed by quagga mussels and their close cousins, zebra mussels, through outreach efforts and occasional voluntary inspections by a specially trained mussel-sniffing dog named Popeye.

The friendly Lab inspected at least 250 vessels between the two reservoirs over eight days this summer, mostly at Lake Sonoma, said Debi DeShon, who provides Popeye’s services through her Central Valley business, Mussel Dogs.

Many boating regulars know the 5-year-old pup by name, including at least one who turned up one day last week and found the chocolate-colored dog ready to work. DeShon reports that most boat owners are happy to comply with inspections.

“Hey, I’m all for it,” Santa Rosa resident Lonny Beaudoin said Thursday as Popeye sniffed around the boat and trailer hitched to his family’s truck.

“It seems like a reasonable way to correct things,” said another owner, Ernest Van Hemert, also of Santa Rosa.

But while Popeye and his handlers have helped spread word of the mussel threat and accustomed boaters to the idea of inspections, a more formal program could be drastically different.

It’s likely, for instance, to result in narrower, daytime launch windows; prohibitions on live bait kept in water; and wait times during peak hours, at least at the start, organizers say.

Mussel inspectors typically have to examine anything that might be wet — from trailer tires and axles, to boat hulls and propellers, to bilges and motor cooling systems, as well as flotation devices, waders, oars and other equipment on board.

If there’s any sign of mussels or larvae, a vessel must be decontaminated or quarantined and notice given to the Department of Fish and Wildlife.

On the North Coast, the plan is to permit frequent boaters who use only one or both of the local reservoirs to avoid inspection with every launch by using snippable bands, which attach to a boat and trailer and, if still intact on arrival at a boat launch, would allow the owner through without further examination.

In any case, the Army Corps of Engineers, which operates the two lakes, will have to enact some restrictions on launch times, both to ensure inspectors are on duty whenever a boat comes through and so all inspections are conducted during daylight hours. Currently, boats can launch any time of day.

But there’s little value to the campaign, they said, unless the goal is zero tolerance and inspections at all launch ramps.

“If just one boat comes in at 11 at night and it has veligers (the mussel larvae) on it, what’s the point?” said Chris Schooley, supervisory ranger at Lake Mendocino for the Army Corps of Engineers.

“You have to have control of the lake,” said Marshall Pike, project director for Quagga Inspection Services, which is consulting on the North Coast plan.

On an early holiday weekend spent enforcing Santa Clara County’s inspection program, upon which Sonoma County’s is being modeled, “we failed 60 percent of the boats,” said Pike, who developed that program and trained those inspectors, as well.

Boats found to contain any water or even be wet weren’t permitted to enter the lakes, period, he said.

“There were a lot of mad people. There were a lot of, ‘How can you do this to us! You just spoiled our weekend’ — all the things you never want to hear,” Pike told a roomful of North Coast agency staffers last week.

But boaters quickly got the drill down in Santa Clara County, which runs inspections at five lakes and reservoirs, he said. Owners now know to show up with their vessels in compliant condition — known among those engaged in the campaign as “clean, drained and dry.”

Partners and stakeholders in the North Coast consortium include the Army Corps of Engineers, the Sonoma County Water Agency, the Mendocino County Russian River Flood Control and Water Conservation Improvement District, the Marin Municipal Water District and the counties of Sonoma, Mendocino, Humboldt and Napa, as well as the Lake Sonoma and Lake Mendocino marinas.

But the challenges of keeping the prolific shellfish at bay are daunting.

The crescent-shaped mollusk, about the size of a fingertip, can attach to practically any surface and can survive for days outside the water, hitchhiking easily aboard a boat or trailer, wildlife agencies say. An adult mussel can produce a million microscopic larvae a year that can exist and travel undetected in even small amounts of water, spreading overland to uninfected lakes and reservoirs.

Native to Eastern Europe, the mussels are believed to have reached North America around 1989 through the Great Lakes via ballast water in European cargo ships.

They were discovered east of the Continental Divide for the first time in 2007, in Lake Mead, and have since taken root in numerous Southern California water bodies, particularly in San Diego and Orange counties, as well as San Bernardino and Riverside.

The northernmost point of their migration so far is San Justo Reservoir near Hollister, just on the other side of Santa Clara County and close enough to give North Coast officials pause.

“We have boaters that commute from San Benito and Santa Clara counties coming into our waterways in Lake Sonoma and Lake Mendocino,” McGuire said. “These two lakes are destination lakes for recreational boaters.”

Once introduced, the mussels can quickly overtake a body of water, altering the food web and starving native species, reducing oxygen levels and changing the water’s acidity in ways that put other wildlife at risk.

In addition, they pose an extreme risk to flood control and water delivery systems such as those that serve about 600,000 users dependent on water from Lake Sonoma, as well as the coho salmon brood stock program at Warm Springs Dam, the Sonoma County Water Agency said.

Details of the local prevention program haven’t been finalized and will be dependent, in part, on the degree of success consortium partners experience in acquiring funding for the program.

About $2.5 million — far less than early estimates ranging as high as $8.5 million — is available to help fund inspections and other programs designed to combat the invasive mussels, thanks to a new $8-per-year boat licensing fee collected under state legislation passed in 2012.

The Sonoma County Water Agency is planning to apply for the maximum two-year grant of $200,000, and the Mendocino County Russian River Flood Control district may do so as well. The deadline is Oct. 20.

Inspections would then be rolled out for a “soft opening” to help boaters become accustomed to them before the start of boating season May 1, organizers said.

“Just like any new program, there will be an adjustment,” McG uire said, “but it will become business as usual.”

You can reach Staff Writer Mary Callahan at 521-5249 or mary.callahan@pressdemocrat.com.